Automatic darkening liquid crystal protective shields, also known as automatic darkening filters, or ADFs, are often used for applications like welding where protection from intense levels of incident light is desired. A typical ADF includes electronic control circuitry, powered by a battery, which causes the filter to change from a light (clear or transparent) state when not subjected to the glare of the welding arc to a dark (nearly opaque) state upon exposure to such glare. This enables a welder to perform a welding operation and also perform tasks outside the welding area without removing the protective shield. The ADFs may be constructed from a combination of polarizing filters and layers of liquid crystal elements. Examples of such filters are described in U.S. Pat. Nos. 6,097,451 and 5,825,441, both to Hornell and Palmer.